Onihei Hankachō (鬼平犯科帳) is a series of historical novels written by Japanese author Shōtarō Ikenami. Following the character Heizo Hasegawa in the Edo period of Japan, Ikegami wrote the first story for the December 1967 issue of the light novel magazine published by Bungeishunjū. It was well-received and began serialization in January 1968. Ikenami wrote 19 books in the main series before he died in 1990. As of 2021, the series had 30 million copies in circulation.